1. Field of the Invention
The invention relates generally to methods for camouflaging articles including articles of clothing and the like and to camouflaging patterns, the invention relating particularly to methods and articles so produced for increasing the camouflaging effect of a camouflaging pattern by changing the chromic state of materials forming at least some of the camouflaging pattern on exposure to changing ambient light conditions.
2. Description of the Prior Art
Camouflage is an art unintentionally but advantageously employed in nature to conceal by pattern and/or color. Mankind learned basic camouflaging techniques from natural sources long prior to recorded history in order to conceal human beings, their possessions and even dwellings from human enemies as well as from animals being hunted or possibly hunting human beings. In more recent times, camouflage has been commonly employed in sport hunting and in military situations, these differing applications sharing a common intent of concealing people, clothing, armament and other accessories through the use of patterns and color which cause the concealed entities to merge with a given background. Camouflaging patterns presently in use vary widely but usually involve representations of natural structure taken from a given environment with which the hunter intends to blend. Such structure includes vegetative materials in particular, whether as individual leaves, stems, branches or the like or vegetative groupings which can be representative of one or more bushes, trees, etc. These patterns are often colored with a number of different colors depending upon the background with which a particular pattern is intended to blend. Such patterns are typically formed by the screening of individual colors in succession on a substrate such as a textile substrate. Even when a variety of colors are employed in an original printed camouflaging pattern of this kind, the color intensity and color type does not change to produce an improved camouflaging effect when the camouflaging pattern is exposed to increased ambient light conditions such as occurs, for example, when the sun comes out from behind a cloud. In prior art camouflaging patterns, the reflective capacities or capabilities of the colors forming portions of the camouflaging pattern do not change since a given color in the camouflaging pattern remains that color regardless of ambient lighting conditions. Given this characteristic of prior art camouflaging patterns, it is readily seen that such prior art patterns do not allow for changes in the colors forming the pattern when the pattern is exposed to increased lighting levels such as are primarily due to changing sunlight conditions. Even more clearly, prior art camouflaging patterns do not provide for changes in the patterns themselves when the pattern is exposed to increasing levels of sunlight. Essentially, except for possible minor changes in color shading brought about by reflectivity only when a prior art camouflaging pattern is exposed to increased ambient light levels, the prior art does not encompass in its teachings a change in a camouflaging effect, much less an improvement in a camouflaging effect brought about by differing ambient light conditions and particularly sunlight exposure levels. In effect, prior art camouflaging patterns remain essentially the same regardless of sunlight intensity.
Photochromic materials are well known in a variety of arts and include light and/or heat sensitive dyes and/or inks both inorganic and organic including polymeric materials, microencapsulated materials and paints inter alia, which materials can be solvated in water-based or other solvents. A characteristic common to photochromic materials is the ability to change chromic state between at least two different light levels. A chromic state is that color condition, including a colorless condition, which exists at a given light level or levels. As an example, a photochromic dye can be essentially colorless at ambient light conditions such as would exist indoors out of direct sunlight but would change to a colored state when exposed to increased ambient lighting conditions such as direct sunlight and/or when exposed to increased heat levels. Photochromic dyes such as "chromasome inks" are particularly available which exhibit colorless chromic states at ambient lighting conditions such as would exist indoors out of direct sunlight but which change chromic state to a colored condition when exposed to direct sunlight, these dye materials having previously been used in articles of apparel such as "T" shirts and the like to produce a colored pattern on the article of clothing when the wearer is in direct sunlight but which "disappears" when the article of apparel is worn indoors in normal indoor ambient light conditions. As such, the prior utility of photochromic dyes and inks of this type has been to produce a highly visible and recognizable pattern on an article of apparel when that article of apparel is exposed to direct sunlight, such articles of apparel and the patterns thus formed thereon being the literal opposite of camouflage since such prior art patterns are intended to be seen.
The present invention intends the provision of methods and articles produced by the methods for increasing the camouflaging effect of any camouflaging pattern by virtue of coating of at least portions of the camouflaging pattern with a photochromic material capable of different chromic states under differing ambient light levels. The camouflaging patterns produced according to the invention are intended to change color and even shape due to color change and when the patterns are exposed to differing ambient light levels and particularly to direct sunlight as opposed to indirect sunlight. Still further, the invention intends the formation of "shadows" and the like in a camouflage pattern such as in areas of the pattern not previously colored or not previously bearing indicia, the shadowing being formed as representational of the manner in which shadows are formed in nature. The invention therefore intends an improvement in camouflaging effect for articles provided with a camouflage pattern produced according to the invention.